Hi everybody, I have been struggling with a problem for a few hours now. Basically, what I am trying to do is set a default value to variable1 in a first rule. Then executes an other rule that checks the value of variable1 and set variable2 to a specific value under some conditions. Right now, my rules go like this : rule "First rule: default" salience 10 lock-on-active true when $myObject : MyObject() then modify($myObject) { setVariable1(defaultValue); } end rule "Second rule" salience 0 lock-on-active false when $myObject : MyObject(variable1 == defaultValue) then $myObject.setVariable2(value2); end When those rules are executed, an exception is thrown : org.drools.runtime.rule.ConsequenceException: rule: First rule: default ... Caused by: java.lang.NullPointerException When I remove the "modify" in the first rule, the exception is not thrown but obviously the second rule is not properly executed ... What is the problem ? What am I doing wrong ? Thanks for your help! Vak' -- View this message in context: http://drools.46999.n3.nabble.com/ConsequenceException-when-using-modify-... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

The initial value is null The setter is a regular one, it really does set the variable1 which is actually a "String". defaultValue comes from a global variable. It is a String that can be correctly printed when the value is set... I really don't understand what is wrong here :s ! -- View this message in context: http://drools.46999.n3.nabble.com/ConsequenceException-when-using-modify-... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

That's not what is in the doc: Documentation wrote > > All operators have normal Java semantics except for == and !=. > The == operator has null-safe equals() semantics: > // Similar to: java.util.Objects.equals(person.getFirstName(), "John") > // so (because "John" is not null) similar to: > // "John".equals(person.getFirstName()) > Person( firstName == "John" ) > And still, actually the MyObject class is actually wrapper to the ActualObject class. The getters and setters are basically simple wrapped. -- View this message in context: http://drools.46999.n3.nabble.com/ConsequenceException-when-using-modify-... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users